Ductal carcinoma in situ localization. This is a DCIS lesion from A) an ER- patient with central necrosis. Note the regionally adjacent vessels outside the lesion (blue arrows) and B) the enlarged image of the central necrosis localized under the black arrow. C) DCIS from an ER + patient without central necrosis despite the size and distance from the center to vasculature; D) as illustrated by the lack of necrosis in the enlarged region uder the black arrow. E) Shows a large (>1 mm) DCIS sample with interior vasculature. This sample does not exhibit necrosis and this patient is ER+. Top row scale bars = 250 μm; bottom row scale bars = 100 μm.